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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I like this idea.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Would you want to somehow figure out which stations have more than one I-gate available (and preferably with different internet providers)? The blackout you may be trying to illustrate could be showing an i-gate outage or an internet outage if you are not trying to look at the data strictly off air.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I would think though that most APRS stations have some sort of battery power that would delay or mask any blackout areas.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>One idea for your display if this does seem to illustrate what you want; in the GIS/mapping software world we can create a polygon using the encompassing points. For your purposes this would more quickly illustrate the possible area of issue. You might also set a parameter of a certain number of points to be required before drawing the polygon. This would help minimize anomaly data.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thank You,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Brian N2KGC<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> aprssig [mailto:aprssig-bounces@tapr.org] <b>On Behalf Of </b>Robert Bruninga<br><b>Sent:</b> Thursday, September 08, 2016 8:17 PM<br><b>To:</b> TAPR APRS Mailing List<br><b>Subject:</b> [aprssig] FEMA - APRS Blackout data wanted...<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>The Technology Office at FEMA asked me about using APRS data... THey want DATA on anything they can get. For example, to visualize power blackouts.<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>I answered "It's in there!"<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>All we have to do is plot it.<o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'>Here is an approach I would try for any WEB based APRS map displays.<o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'>1) Keep at least 5 bits on every WX and HOME station and DIGIPEATER<o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'>2) Every 11 minutes decrement every such stations counter by 1<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>3) Every time a new packet is heard, increment the counter by 10<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>Now then any station with a count greater than 9 is considered a >90% reliable 24/7/365 station (has been heard in the last 30 minutes too) We can call these 24/7 stations.<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>Now when someone asks for a BLACKOUT PLOT, display two things:<o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'>All stations that have been heard in the last 10 minutes... (live stations)<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>AND *greyed-out* symbols for all of the 24/7 stations (blackout stations) that have not been heard in 30 minutes.<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>BINGO, done. We have the data, just need to come up with the right algorithm and the best way to display it.<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>The original APRSdos sort of did this by fading-to gray all stations not heard in the last X minutes, This worked great locally because we each generally knew all the symbols there were normally there 24/7 and conuld instantly visualize something was wrong when they all faded to gray in an area. (but were still on the map)<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>But for huge APRS-IS systems, there needs to be the algorithm to know which stations area always on, so they can then indicate when the disappear..<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>Sure, lots of reasons why this is not going to be pergfect, but it does give a QUICK indication that something has changed and eeds further investigation...<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'>Hessu? Steve? <o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'>Bob<o:p></o:p></p></div></div></body></html>